The present invention relates to a printing apparatus having a power saving function (sleep mode) for suppressing power consumption in a non-printing state, a system having the same, and a method of controlling the printing apparatus.
In recent years, printing apparatuses of this type, e.g., page printers represented by laser beam printers have become rapidly widespread.
Generally, an apparatus of this type is constituted by a printer controller for receiving printing data to generate a printing image and at the same time controlling the entire apparatus, and a printer engine for actually performing printing. Since the printer engine has a thermal fixing unit, the power consumption is undesirably increased.
For this reason, in a printing standby state, in other words, when a predetermined period of time has elapsed after supply of printing data from a host unit (e.g., host computer) is cut off, power to the printer engine, particularly to the thermal fixing unit is stopped, thereby appropriately suppressing the power consumption. That is, this printer has a sleep mode (or power save mode).
Setting and canceling of the sleep mode are controlled by the printer controller (CPU in the printer controller). More specifically, upon power-on, or when a predetermined period of time has elapsed after completion of printing processing, and no further printing data is received, power supply to the printer engine is stopped. If printing data is received in the sleep mode, power supply to the printer engine is resumed.
Although the power consumption can be surely reduced in the sleep mode as compared to an actual printing mode, power supply to the printer controller never stops. Additionally, the CPU and various circuits requiring a large power consumption are connected to the printer controller through buses. Taking these factors into consideration, no sufficient power saving effect can be obtained yet.
The present invention has been made to solve the above problem, and the first to eighth inventions according to the present invention have as their object to provide a printing apparatus in which an interface section for performing communication processing with-a host unit is separated from a controller section, and the interface section controls the power supply states of the controller section and a printer engine section to control the power supply states of the controller section and the printer engine section, both of which have a large power loss, such that the printing apparatus itself further saves power consumption in a sleep state while ensuring a communication state with the host unit.
The first invention according to the present invention comprises an interface section for performing data communication with a host unit, a controller section for generating a printing image based on printing data sent from the host unit through the interface section, an engine section for performing recording on a recording medium on the basis of the printing image from the controller section, and a power supply for always supplying power to the interface section while a power supply switch is in an ON state, wherein the interface section has control means for controlling power supply from the power supply to the controller section and the engine section on the basis of data received from the host unit.
In the second invention according to the present invention, the control means controls power supply such that power supply from the power supply to the controller section is started upon reception of a predetermined command from the host unit, and power supply from the power supply to the controller section is stopped upon reception of a predetermined command from the controller section.
In the third invention according to the present invention, the interface section has informing means for informing a status of a printing apparatus main body to the host unit.
In the fourth invention according to the present invention, the interface section communicates with a plurality of host units through a network.
In the fifth invention according to the present invention, the host unit preferentially selects a printing apparatus whose printing apparatus main body is set in a standby state, which is informed by the informing means, before a printing apparatus in a sleep state.
In the sixth invention according to the present invention, when the host unit recognizes that a plurality of printing apparatuses are set in the standby state, the host unit sends a command for setting one of the printing apparatuses in the sleep state to the interface section.
In the seventh invention according to the present invention, the interface section can be freely attached/detached to/from the printing apparatus main body.
In the eighth invention according to the present invention, the interface section can be externally connected through an external interface port of a printing apparatus main body.
In the first invention according to the present invention, the control means of the interface section controls power supply from the power supply to the controller section and the engine section on the basis of data received from the host unit to limit power supply to the controller section and the engine section in the sleep state except for power supply in the interface section, thereby further saving power.
In the second invention, the control means controls power supply such that power supply from the power supply to the controller section is started upon reception of a predetermined command from the host unit, and power supply from the power to the controller section is stopped upon reception of a predetermined command from the controller section. In accordance with a command from the host unit, the state of the printing apparatus can be reversibly switched from the sleep state to the standby state or from the standby state to the sleep state.
In the third invention, the informing means of the interface section informs the status of the printing apparatus main body to the host unit such that the host unit can properly determine the current printer status of the printing apparatus.
In the fourth invention, the interface section communicates with the host unit through a network. Upon reception of a command from any one of the host units, power supply to the controller section and the engine section in the sleep state can be limited except for power supply in the interface section, thereby further saving power.
In the fifth invention, in accordance with information from the interface section, the host unit preferentially selects a printing apparatus whose printing apparatus main body is set in the standby state before a printing apparatus in the sleep state, thereby determining a printing apparatus capable of performing printing processing as quickly as possible.
In the sixth invention, when the host unit recognizes that a plurality of printing apparatuses whose printing apparatus main bodies are set in the standby state are present, the host unit sends a command for setting one of the printing apparatuses in the sleep state to the interface section. With this operation, regardless of changes in status of each printing apparatus, a printing apparatus capable of performing printing processing can be determined as quickly as possible while printing apparatuses not subjected to printing are set in the sleep state.
In the seventh invention, the interface section can be freely attached/detached to/from the printing apparatus main body, thereby coping with expansion or modification of the interface section.
In the eighth invention, the interface section can be externally connected through the external interface port of the printing apparatus main body, thereby externally expanding the function of the interface section to a conventional printing apparatus.
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.